nanogui: XOR not working for strings in FLTK
Subject:
Re: [nanogui] XOR not working for strings in FLTK
From:
"Greg Haerr" ####@####.####
Date:
7 Feb 2011 23:35:11 -0000
Message-Id: <100c01cbc71f$98405e60$0300a8c0@RDP>
> The line drawing works (XORes) but string printing does not XOR, just
> copies.
Martin, you're running the 0.92 official release from 11/2010 of
NXLIB and Microwindows, and line drawing XOR works, but
text drawing not, right?
The 0.92 release was cut in November from the June 2010
codebase, just before the major driver changes were made.
In 0.92, line draws use linear16_drawpixel, which implements XOR
with the APPLYOP macro.
Text output uses two different routines, depending on whether the
text is anti-aliased (freetype/truetype), or bitmap (PCF/FNT/Core).
In both these cases, I think I had included the faster blit routines
to be used for outputting text. This is either linear16_drawarea for
anti-aliased text, or corefont_drawtext for bitmap drawing.
I don't think the latter had XOR support, the former may not either.
The 0.92 text output tries to use the porter-duff SRCOVER compositing
operation for text output for proper anti-aliased drawing, rather than
raster operations. I need more info about your font in order to
help.
After 0.92 was released, and currently in the git repo are heavily
rewritten routines that use a new conversion blit architecture for
all image output, including text, GrArea, images etc. XOR is
fully supported in the blit routines, but still may be overridden by
SRCOVER for text output. I will have to look more into this when
I can check the source.
Regards,
Greg
